ELECTRICAL DISTRIBUTION SYSTEM

Abstract: An electrical distribution assembly (11) includes an elongate flexible insulated housing (12) having a plurality of longitudinally extending slots (13-16), one slot (16) being in a face opposed to the face containing the other slots (13-15) each of which carry a conductor in the form of a hollow coil. The arrangement is such that the width of the slots decrease when the assembly is bent perpendicular to the slots. A connector for the distribution assembly is also provided. It has a plurality of tines, with associated socket means, to contact the hollow coil conductors. The tines, when received in the housing, are rotated to establish electrical contact. The hollow coil may be made from flat conductive material and the housing, in another embodiment, may substantially fill the core of a coiled hollow conductor and extend through the coils to form a longitudinally extended insulation portion. At least one longitudinal portion of the conductor is exposed for electrical contact.

Description: "ELECTRICAL DISTRIBUTION SYSTEM" Technical field This invention relates to an electrical conductor, a flexible conductive track, electrical connector and electrical distribution system. The invention has particular but not exclusive application to an electrical conductor, a flexible conductive track, electrical connector and electrical distribution system for use in walls, floors, ceilings, skirting boards and the like for distribution of electrical power and/or electrical signals. Background Art It is known for to provide flexible conductive track for such purposes. International application PCT/AU92/00414 in the name of Mass International Pty Ltd is an example of a known flexible conductive track. The invention of International application PCT/AU92/00414 provides an insulating housing adapted to be bent at right angles without the need to provide corner adaptors. The housing of International application PCT/AU92/00414 has a plurality of longitudinally extending recesses which close when the flexible conductive track is bent in the manner illustrated in FIGS 8 to 10 of International application PCT/AU92/00414. The flexible conductor illustrated in FIG 11 of International application PCT/AU92/00414 is a solid copper wire supporting a conductive blade having cutouts along its length. Summary of invention The present invention aims to provide an alternative electrical conductor, flexible conductive track, electrical connector and electrical distribution system which will be reliable and efficient in use. This invention in one aspect resides broadly in an electrical bus distributor assembly including:- an elongate flexible insulated housing; a longitudinally extending slot in the housing, and an elongate flexible conductor assembly located in the slot, the conductor assembly comprising a coiled hollow conductor. In a preferred embodiment the elongate flexible insulated housing has a plurality of longitudinally extending slots extending inwardly from one face thereof, a coiled hollow conductor being located in at least one of the slots in the one face, and at least one longitudinally extending slot extending inwardly from a substantially opposite face thereof; the arrangement being such that the width of the slots decrease when the bus distributor assembly is bent in a plane substantially perpendicular to the slots. The coiled hollow conductor may be either a closed coil or an open coil and may be formed from substantially flat conductive material. As used herein the expression " flat conductive material" includes strip-like and ribbon-like material. The coiled hollow conductor may be a single strand or may be formed from a plurality of strands. The coiled hollow conductor may be retained within the slot by any suitable means. This could be by adhesives or by ultrasonic welding. In one preferred embodiment the electrical bus distributor assembly includes fastening means for fastening the coiled hollow conductor in the slot. The fastening means may be staples adapted to engage the coiled hollow conductor or elongated coils of the coiled hollow conductor. Alternatively the fastening means may be pins in electrical contact with and supporting the coiled hollow conductor. In another preferred embodiment the fastening means may be a portion of the insulated housing co- extruded with the coiled hollow conductor. A portion of the insulated housing may substantially fill the core of the hollow conductor and extend through the open coils thereof to form at least one longitudinally extending insulated portion along the exterior of the hollow conductor. In another aspect this invention resides broadly in an electrical connector for connection to an electrical bus distributor assembly as defined above, the connector including:- a support member; a plurality of tines extending radially from the support member; a plurality of socket means respectively associated with the tines for establishing electrical contact with a respective coiled hollow conductor; the arrangement being such that the tines are receivable within an access channel adjacent the distributor assembly to prevent the electrical contact being established, the electrical connector being rotatable within the access channel to establish the electrical contact. It is preferred that one of the socket means makes electrical connection with an earthed conductor in the distributor assembly upon rotation of the connector before the others of the socket means make electrical connection respectively with the others of the coiled hollow conductors. The socket means may be adapted to releasably engage the coiled hollow conductors and to be restrained thereon and may also include rotation limiting means adapted to prevent rotation of the electrical connector beyond an orientation wherein the tines are substantially perpendicular to the coiled hollow conductors. The rotation limiting means could be an abutment adapted to engage with a stop located on the bus distributor assembly or could be other suitable means. However it is preferred that the rotation limiting means is a cam having stop means. The cam may be a peripheral flange on the support member and the stop means may be a tangential extension of the peripheral portion of the flange. In another preferred embodiment the electrical connector includes a guard assembly pivotally mounted on the support member and adapted to pivot from a position substantially encompassing the tines and the socket means upon engagement of the guard assembly with the bus distributor assembly upon rotation of the connector. The rotation limiting means may include a pin and a slot one of which is associated with the guard assembly and adapted to rotate therewith. In a preferred embodiment the abutment of the rotation limiting means is a pin on the guard member adapted to pivot therewith and the stop is an arcuate slot in the connector housing. Alternatively the pin can be on the housing and the slot on the rotation limiting means. In a further aspect this invention resides broadly in an electrical distribution system including:- a support housing having at least one longitudinally extending chamber for receiving and supporting an electrical bus distributor assembly; an electrical bus distributor assembly as defined above located in the chamber and spaced from a wall of the chamber to define a substantially continuous longitudinally extending access channel therewith, and at least one electrical connector having a plurality of socket means for establishing electrical contact with a respective coiled hollow conductor, the arrangement being such that the socket means are associated with tines receivable within the access channel to prevent the electrical contact being established, the plug assembly being rotatable within the access channel to establish the electrical contact. In yet another aspect this invention resides broadly in an electrical distribution system including:- a support housing having at least one longitudinally extending chamber for receiving and supporting an electrical bus distributor assembly; an electrical bus distributor assembly as defined above located in the chamber and spaced from a wall of the chamber to define a substantially continuous longitudinally extending access channel therewith, and an electrical connector as defined above and adapted to be received within the access channel. In a still further aspect this invention resides broadly in a method of electrical distribution including:- providing a support housing having at least one longitudinally extending chamber for receiving and supporting an electrical bus distributor assembly; locating an electrical bus distributor assembly as defined above in the chamber and spaced from a wall of the chamber to -define a substantially continuous longitudinally extending access channel therewith; locating an electrical connector as defined above in the access channel, and rotating the electrical connector. In another aspect this invention resides broadly in an elongate flexible conductor assembly including:- an open coiled hollow conductor, and an insulating member substantially filling the core of the hollow conductor and extending through the open coils thereof to form at least one longitudinally extending insulated portion along the exterior of the hollow conductor; wherein the exterior has at least one longitudinally extending exposed surface not covered by the insulating member for the establishment of electrical contact with the conductor. In another aspect this invention resides broadly in an elongate flexible open coiled hollow conductor formed from substantially flat or ribbon-like conductive material. Description of the drawings In order that this invention may be more easily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate a preferred embodiment of the invention, wherein:- FIGS 1 to 4 are perspective views of an electrical distribution system in accordance with the invention, illustrating the manner of establishing an electrical connection; FIGS 5 and 7 are perspective views of an electrical distributor in accordance with the invention; FIG 6 is a perspective view of a pronged fastener for fastening a conductor within the housing; FIG 8 is a perspective view of a close coiled conductor in accordance with the invention; FIG 9 is a side view of an open coiled conductor in accordance with the-invention; FIG 10 illustrates the tension and compression of a coiled conductor when bent; FIGS 11 to 19, and FIGS 30 and 31 are illustrations of various coiled conductors including arrangements for locating the conductors in the housing; FIG 20 is a side view of another open coiled conductor in accordance with the invention; FIGS 21 and 22 are side and end views respectively of one form of an electrical connector in accordance with the invention; FIGS 23 and 24 are end and side views respectively of another form of electrical connector in accordance with the invention; FIG 25 is a cross-sectional elevation of an electrical distribution system located in a skirting board; FIG 26 is a cross-sectional elevation illustrating a plug connected in the electrical distribution system; FIG 27 illustrates the incremental electrical connection during rotation of the electrical connector; FIG 28 illustrates an electrical distribution assembly located in a floor; and FIG 29 illustrates an electrical distribution assembly located in a ceiling for track lighting or the like. Description of the preferred embodiments The mechanical operation of the electrical distribution assembly is explained in international application PCT/AU92/00414. As can be seen in FIG 5, a flexible conductive track 11 includes close coiled hollow conductors 17 mounted or otherwise fastened at the ends of longitudinally extending slotted recesses 13 to 15 formed in an insulating housing 12. A further slotted recess 16 is located opposite central recess 14. The coiled hollow conductors 17 are preferably made from copper or aluminium. The close coiled conductors can be fastened within the slotted recesses by means of staples 18 illustrated in FIG 7. The staples are channel shaped with a pair of pronged arms 19 and 20 extending from a base 21. Staples 21 engage the conductors through longitudinally extending slots 22 or, as can be seen in FIG 6, through transverse slots 23. In the former case the conductors are fastened by the prongs locating between the conductor coils, whereas in the latter the conductors are fastened by the pronged arms clamping over the outer surface of the coiled conductor. Alternatively as seen in FIGS 13, a close coiled hollow conductor 34 has regularly spaced larger loops 35 adapted to pass through slotted openings in the top of housing 16 and be bent over to retain conductor 34 therein. FIG 14 illustrates this arrangement with an open coiled conductor. The loops can be twisted (not shown) to add rigidity to the coil. As can be seen in FIG 9, an open coiled hollow conductor 24 is also suitable. As will be seen from reference to FIG 10, when a coiled hollow conductor is bent through an angle such as a right angle as illustrated, one side 28 of the coil extends in tension and the other side 27 compresses. As can be seen in FIG 12, the coiled conductor can be a single strand 60 or as illustrated in FIG 11, coiled conductor 55 can be multi-strand conductor made of a number of individual strands 56 to 59. Consequently the current carrying capacity of the coil can be increased by increasing the number of strands whilst at the same time maintaining the diameter of both the wire and the coil to a selected design minimum. Alternatively as can be seen in FIG 15, a coil conductor 61 can be threaded into an apertured plastic former 62 which is adapted to be attached within the insulated housing by heat, chemical or ultrasonic welding or other suitable fixing means. FIGS 16 to 18 respectively illustrate coil conductors 63, 65 and 67 which are associated with pins 66 by welding or soldering (FIG 17), wires 64 which are fitted and twisted (FIG 16), and L-shaped lugs 68 fitted into the coil (FIG 18). Alternatively, as can be seen in FIG 19, coil 69 may be reduced at section 70 and an attaching wire (not shown) fitted and twisted. FIG 20 illustrates an open coil conductor 71 in the form of a coiled length of substantially flat material formed by roll flattening a length of round conductive material and coiling the flattened length to the desired diameter. Coiled "ribbon" strip gives a smaller coiled diameter than coiled "round" for the same cross-sectional area of conductor. Furthermore the linear length of coiled "ribbon" strip is less than that of an equivalent coiled "round", hence the linear resistance of the coiled length is less. FIG 30 is a cross-sectional elevation illustrating an open coiled conductor embedded in a portion of an insulated housing. A portion of the insulated housing 92 can be co-extruded with coiled conductor 91 to substantially fill the interior of the coiled conductor at 93 and to form an angled guide 94 for assisting alignment of the arms of sockets 33. This method of fastening also enhances the strength and support of the coil. The coiled ribbon strip of conductor 91 provides a greater contact area than a coiled round conductor. Furthermore, the linear resistance, as tested, is less for a coiled ribbon strip than for a similar straight length of round conductor. This indicates a more direct current route through the coiled ribbon strip. Alternatively as seen in FIG 31 which is a cut-away perspective view of an open coiled conductor embedded in a triangulated insulated sheathing, an insulated coiled conductor 95 is provided for affixing to an insulated housing such as illustrated in FIG 7 by chemical bonding, ultrasonic welding, co-extrusion or other suitable method. For example the insulated coiled conductor 95 can be provided in rolls as with conventional conductors, set up on the extrusion cross-head, the number of rolls depending on the nature of the distribution system, ie 2 wire, 3 wire, 4 wire etc, and joined with the housing as it is being extruded. As can be seen in FIGS 21 and 22 a connector plug 29 engages the conductors in manner similar to that described in International application PCT/AU92/00414. Connector plug 29 has legs 30 to 32 carrying electrical connector sockets 33 adapted to snap over coiled conductors 71 as seen in FIG 26. An abutment in the form of a peripheral flange 72 is adapted to bear against the outer casing or skirting board and a flange 73 having a right-angle stop 74 is adapted to prevent the electrical plug 29 overcentering as can be seen in FIG 27. FIGS 23 and 24 illustrate an alternative connector having a guard 75 mounted on a pivot 96 and attached to the connector to be free to rotate relative to the legs. In use the guide 74 both protects the tines and guides them during turning within the bus assembly. As can be seen in FIG 27 the arrangement is such that the earth conductor on leg 32 is engaged first during pivoting of the plug. Correspondingly during removal of the electrical connector from the electrical distributor, the earth conductor is the last to be disengaged. Flange 73 provides a camming action which stops when right-angled stop 74 engages with a mating surface on the distributor assembly or skirting board whereby rotation of the plug beyond the 90° point is prevented. This is also facilitated by the provision of a pin 97 on pivot 96 adapted to rotate with guard 75 within a quadrant arcuate slot 98 located in the wall 99 of plug housing 53. The slot is oriented so that the tines do not rotate through more than 90° from the disconnected to the connected positions. As can be seen in FIG 25, the bus distributor assembly 76 is supported within skirting board support housing 78. Cover piece 77 supports the distributor assembly 76 and a cover strip 79 fits within an access channel beneath the bus distributor 76 which, in use, receives the electrical connector. Duct cover 80 covers duct 93. Longitudinally extending ribs 81 are located on the interior wall of the housing 78 and serve to prevent inadvertent or accidental insertion of flexible objects into the housing. This enhances safety and guards against accidental electrocution of young children inserting electrically conductive material into the bus distributor assembly. FIG 26 illustrates a connector plug 53 positioned in the distributor assembly and rotated through 90° to establish electrical contact. The distributor assembly illustrated in FIG 26 extends away from wall 82 comparison with that illustrated in FIG 25 where the assembly is flush with wall 82. As can be seen in FIG 28, a distribution assembly 87 may be located in the floor 84 to be flush with carpet 86 above underlay 85. Alternatively, as seen in FIG 29, a bus distributor assembly 88 may be located in ceiling 89 with connector 91 providing power to an electric light 90. In use as can be seen in FIGS 1 to 4, flexible conductive track is located in skirting board 50. Cover strip is cut at 52 to leave a gap. Electrical connector 53 attached to electrical lead 54 is inserted in gap 52 as seen in FIG 3 and rotated through 90° as seen in FIG 4 . It will be appreciated that in use the flexible conductive track can be bent through a substantial angle and the coiled hollow conductors will on one side be compressed and on the other be extended without permanent distortion because of the inherent resilience of the coiled hollow conductor. The electro magnetic field associated with the coiled hollow conductor is more concentrated than that of a straight conductor thereby decreasing level of interference caused to data cabling by conventional electrical power distribution systems. It will also -be appreciated that the electrical distribution system in accordance with the present invention has other advantages. The distribution assembly can be a single or a multi-level cassette so that it is possible to add additional cassettes within a single housing to distribute a range of electrical services. For example power in one circuit, audio in another circuit and computer cabling in a third circuit. Because of the concentration of the electro-magnetic field within the coil conductor, coincident housing of a multi-cable system including data and communications systems is feasible. Furthermore, the wiping action of the tines over the conductors provides a self-cleaning effect and removes oxide from the conductor. In use the adaptability of the flexible housing of the present invention to bend through an angle, typically through a right angle or other angles including a 180 degree return, avoids the requirement of prior art systems with rigid conductors to cut and fit adaptors at the corners of a room. The continuity of the conductor assembly results in improved electrical characteristics and also simplifies installation thereby lowering material and labour installation costs. The distribution system of the present invention provides a useful alternative to known systems. It is adaptable for use in floors and ceilings as well as skirting boards, and can be used as a light-track for lighting systems or for transmission of audio signals in sound systems. It will be appreciated that each of the above systems can be incorporated in a multi-chamber housing. The coiled conductor of the present invention is an improvement on the conductor illustrated in International application PCT/AU92/00414 wherein, when bent through substantially a right angle, the inside flexible conductor of the conductor assembly can become kinked because the peripheral extent of the bend on the inside is less than that of the middle and outer conductors. It will of course be realised that whilst the above has been given by way of an illustrative example of this invention, all such and other modifications and variations hereto, as would be apparent to persons skilled in the art, are deemed to fall within the broad scope and ambit of this invention as is hereinafter claimed.

Claims: Claims 1. An electrical bus distributor assembly including:- an elongate flexible insulated housing; a longitudinally extending slot in said housing, and an elongate flexible conductor assembly located in said slot, said conductor assembly comprising a coiled hollow conductor. 2. An electrical bus distributor assembly as claimed in claim 1, wherein said elongate flexible insulated housing has a plurality of longitudinally extending slots extending inwardly -from one face thereof, a coiled hollow conductor being located in at least one of the slots in said one face, and at least one longitudinally extending slot extending inwardly from a substantially opposite face thereof; the arrangement being such that the width of said slots decrease when the bus distributor assembly is bent in a plane substantially perpendicular to said slots. 3. An electrical bus distributor assembly as claimed in claim 1 or claim 2, wherein said coiled hollow conductor is a closed coil. 4. An electrical bus distributor assembly as claimed in claim 1 or claim 2, wherein said coiled hollow conductor is an open coil. 5. An electrical bus distributor assembly as claimed in claim 3 or claim 4, wherein said coiled hollow conductor is formed from substantially flat conductive material. 6. An electrical bus distributor assembly as claimed in claim 3 or claim 4, wherein said coiled hollow conductor is formed from a plurality of strands. 7. An electrical bus distributor assembly as claimed in any one of the preceding claims, and including fastening means for fastening said coiled hollow conductor in said slot. 8. An electrical bus distributor assembly as claimed in claim 7, wherein said fastening means are staples adapted to engage said coiled hollow conductor. 9. An electrical bus distributor assembly as claimed in claim 7, wherein said fastening means are elongated coils of said coiled hollow conductor. 10. An electrical bus distributor assembly as claimed in claim 7, wherein said fastening means are pins in electrical contact with and supporting said coiled hollow conductor. 11. An electrical bus distributor assembly as claimed in claim 7, wherein said fastening means comprises a portion of said insulated housing co-extruded with said coiled hollow conductor. 12. An electrical connector for connection to an electrical bus distributor assembly as claimed in any one of the preceding claims, said connector including:- a support member; a plurality of tines extending radially from said support member; a plurality of socket means respectively associated with said tines for establishing electrical contact with a respective coiled hollow conductor; the arrangement being such that said tines are receivable within an access channel adjacent said distributor assembly to prevent said electrical contact being established, said electrical connector being rotatable within said access channel to establish said electrical contact. 13. An electrical connector as claimed in claim 12, wherein one of said socket means makes electrical connection with an earthed conductor in said distributor assembly upon rotation of said connector before the others of said socket means make electrical connection respectively with the others of said coiled hollow conductors. 14. An electrical connector as claimed in claim 12 or claim 13, and including rotation limiting means adapted to prevent rotation of said electrical connector beyond an orientation wherein said tines are substantially perpendicular to said coiled hollow conductors. 15. An electrical connector as claimed in claim 14, wherein said rotation limiting means is a cam having stop means. 16. An electrical connector as claimed in claim 14, wherein said cam is a peripheral flange on said support member and said stop means is a tangential extension of the peripheral portion of said flange. 17. An electrical connector as claimed in any one of claims 12 to 16, and including a guard assembly pivotally mounted on said support member and adapted to pivot from a position substantially encompassing said tines and said socket means upon engagement of said guard assembly with said bus distributor assembly upon rotation of said connector. 18. An electrical connector as claimed in claim 17, wherein said rotation limiting means includes a pin and a slot one of which is associated with said guard assembly and adapted to rotate therewith. 19. An electrical distribution system including:- a support housing having at least one longitudinally extending chamber for receiving and supporting an electrical bus distributor assembly; an electrical bus distributor assembly as claimed in any one of claims 1 to 11 located in said chamber and spaced from a wall of said chamber to define a substantially continuous longitudinally extending access channel therewith, and at least one electrical connector having a plurality of socket means for establishing electrical contact with a respective coiled hollow conductor, the arrangement being such that said socket means are associated with tines receivable within said access channel to prevent said electrical contact being established, said plug assembly being rotatable within said access channel to establish said electrical contact. 20. An electrical distribution system including:- a support housing having at least one longitudinally extending chamber for receiving and supporting an electrical bus distributor assembly; an electrical bus distributor assembly as claimed in any one of claims 1 to 11 located in said chamber and spaced from a wall of said chamber to define a substantially continuous longitudinally extending access channel therewith, and an electrical connector as claimed in any one of claims 12 to 17 and adapted to be received within said access channel. 21. A method of electrical distribution including:- providing a support housing having at least one longitudinally extending chamber for receiving and supporting an electrical bus distributor assembly; locating an electrical bus distributor assembly as claimed in any one of claims 1 to 11 in said chamber and spaced from a wall of said chamber to define a substantially continuous longitudinally extending access channel therewith; locating an electrical connector as claimed in any one of claims 12 to 17 in said access channel, and rotating said electrical connector. 22. An elongate flexible conductor assembly including:- an open coiled hollow conductor, and an insulating member substantially filling the core of said hollow conductor and extending through the open coils thereof to form at least one longitudinally extending insulated portion along the exterior of said hollow conductor; wherein said exterior has at least one longitudinally extending exposed surface not covered by said insulating member for the establishment of electrical contact with said conductor. 23. An electrical bus distributor assembly as claimed in claim 4, wherein a portion of said insulated housing substantially fills the core of said hollow conductor and extends through the open coils thereof to form at least one longitudinally extending insulated portion along the exterior of said hollow conductor. 24. An elongate flexible open coiled hollow conductor formed from substantially flat conductive material.

Inventors: DRURY LEE ANDREW, DRURY, LEE, ANDREW
Applicants: DRURY LEE ANDREW, MASS INT PTY LTD, DRURY, LEE, ANDREW, MASS INTERNATIONAL PTY. LTD.
Application year: 1994
Main classification: H02G5
IPC codes: H01B5, H01R25, H02G5